The Ottawa River Flowing Towards the Cities of Ottawa and Gatineau, Canada45.4N 75.6W
The Ottawa River runs through the Canadian provinces of Ontario and Quebec, defining the border between these two provinces for most of its length. The total length of the river is 1,271 kilometers (790 mi). It drains an area of 146,300 km2, 65% in Quebec and the rest in Ontario, with a mean discharge of 1,950 m3/s.
The river rises from its source in Lake Capimitchigama in the Laurentian Mountains of central Quebec, flows west to Lake Timiskaming, where it begins defining the interprovincial border with Ontario.
From Lake Timiskaming the river flows southeast to Ottawa and Gatineau where it tumbles over the Chaudière Falls. On the right side of this orthorectified image, the two cities can be seen near its shores. Ottawa, the capital of Canada, lies along the southern banks, with Gatineau parallel to it along the northern banks.